Instructions
Step 1: Prepare the Grated Butter Dough
In a large bowl, whisk together the flour, sugar, and salt. Grate the cold butter directly into the mixture, tossing gently to coat the pieces evenly.
Tip: If the butter starts to soften, place it in the freezer for about 10 minutes. Keeping it cold helps create steam during baking, which forms light, flaky layers.
Step 2: Add Water and Chill
Pour the ice water into the center and mix with a fork until a rough dough forms. Add more water, one tablespoon at a time, just until the dough holds together without becoming sticky. Divide into two portions, shape into rectangles, wrap, and chill for at least 30 minutes.
Step 3: Assemble
Preheat the oven to 400°F. Roll out one portion of dough to fit a 9×13-inch jelly roll pan and press it into place. Spread the apple filling evenly over the crust. Roll out the second portion and place it over the top, sealing the edges by pinching them together.
Step 4: Bake
Cut a few small slits in the top to allow steam to escape. Bake for about 40 minutes, rotating halfway through, until the crust is golden brown. Let cool completely on a wire rack.
Step 5: Glaze and Finish
In a bowl, mix powdered sugar, softened butter, milk, and vanilla until smooth. Spread over the cooled pastry and let it set for about 20 minutes before slicing into squares.
